Pratley argues the joint acquisition of the firm by Buffett's company Berkshire Hathaway and private equity firm 3G – which saw shares in Heinz soar by nearly 20 per cent on Wall Street – could mark the beginning of a deeper relationship between the two companies.

"Buffett was falling over himself to heap praise on 3G leading light Jorge Paulo Lemann," Pratley writes. "Could bagging Heinz also be a prelude to more deals?"

Heinz is Buffett's first significant acquisition since railway company Burlington Northern Santa Fe in 2010 – but Bloomberg's Business Week cautions against any expectations the 82-year-old is about to retire.

The billionaire businessman remains in "good health" despite undergoing treatment for prostate cancer last summer, Bloomberg says, so "Heinz isn't likely to be the last condiment Buffett adds to Berkshire's investment meal".

Buffett himself told CNBC yesterday he remains in the market for further acquisitions, adding he is "ready for another elephant, so if you see one walking by just tell me". It seems he has been planning the deal, which Heinz said was the largest food buyout in history, for some time.

Buffett revealed he's had a file on the firm, famous for its ketchup and beans, since 1980. "It's our kind of company," he said, adding:
"Anytime we see a deal is attractive and it's our kind of business and we've got the money, I'm ready to go."